The UCC28056 device drives PFC boost stages based on an innovative mixed mode method that operates in Transition mode (TM ) at full load and transitions seamlessly into Discontinuous Conduction mode (DCM) at reduced load, automatically reducing switching frequency. This device incorporates burst mode operation to further improve light load performance, enabling systems to meet challenging energy standards while eliminating the need to switch off the PFC. UCC28056 can drive a PFC power stage up to 300 W, ensuring sinusoidal line input current with low distortion, close to unity power factor while keeping the PFC ‘always on’. When used with the LLC controller UCC256301, this 6-pin device eliminates the need for an auxiliary fly back converter, (typically needed in systems for good standby performance) while achieving less than 80 mW at 230 Vac. The device also enables instant turn on while reducing external component count to a minimum.